Prime Minister Jacinda Ardern said Cabinet has decided to update mask mandates for the country as Omicron cases in the community increase.
Today, 10 new Omicron cases were reported and the variant has appeared in Tauranga after earlier being detected in Auckland and Motueka.
Masks must now be worn at businesses which serve food and drink, the PM said.
In practice, diners will now be asked to wear masks when getting up from a table to use the bathroom.
"We're also now requiring that a face covering be an actual mask," Ardern said.
This means the use of T-shirts pulled up over the mouth or other haphazard measures will be discouraged.
Children on publicly-funded school trips will be required to wear face masks, Ardern added.
"These adjustments will slow the spread of the virus."
The new rules take effect on Thursday, February 3.
Ardern said overseas evidence showed face mask use helped combat the spread of Omicron.
The PM encouraged workplaces which were not customer-facing to decide on how to best implement a practical mask use policy.
Ardern said it would be cumbersome to assign people to assess if scarves or makeshift face coverings were properly fitted.
"We are asking for something that connects over your face."
She said the Ministry of Health could advise people on mask use.
"It has to be something that is actually made to be a face covering."
Bloomfield said medical surgical masks, or three-layer masks, or some combination of them, was recommended.
"We're not going to be recommending the use of N95s for the general public."
He said this was partly due to the expense of N95 face coverings.
PCR testing and RATs
The PM said essential workplaces such as those in the health, supply chain and supermarket sectors will get more access to rapid antigen tests (RATs).
"This is to allow a 'test to return to work' approach.
"For now those PCR tests are best," Ardern added.
She said capacity existed for 60,000 tests a day, with surge capacity to nearly 78,000 daily tests.
But more than 40 million RATs kits had been ordered.
Ardern said nine rapid test types were already approved for use but various types had widely differing degrees of accuracy.
Ardern confirmed Associate Minister of Health Dr Ayesha Verrall would provide more information on the next stage of the pandemic response tomorrow.
Dr Ashley Bloomfield joined Ardern at the press conference and discussed RATs tests and orders.
"The challenge is getting confirmation of delivery ... against those orders."
He said RATs would probably be more widely used in the second and third stages of the Omicron response.
Ardern said if Omicron cases grew, rapid tests would be used more often.
Ardern said a surge in PCR testing capacity was independent of any rapid test issues, and not compensatory for a lack of RATs kits.
"In this early stage, when we're stamping it out and seeking to stamp it out, PCR remains our best solution."
Ardern said more information on a "test to return to work regime" would be outlined tomorrow, as would details on how the penultimate and final stages of the Omicron response would be managed.
The PM said high case numbers in an Omicron outbreak would lead to high exposure and contact numbers, and subsequently on critical workforce members.
Bloomfield said the Omicron response regime would involve the Government helping more businesses access RATs kits.
Ardern said testing regimes should be honed to ensure the people most likely to need tests could get tests.
"We don't want someone staying at home when they don't need to," the PM said.
Asked about critical workers, Ardern said the Government wanted to offer essential workers and their employers as much support as possible, but the expansion of rapid test use would be no substitute for prevention measures such as mask use.
"A rapid antigen test is a test. It's not a preventative measure."
On antiviral drugs, Bloomfield said orders had already been placed for Remdesivir and Paxlovid.
"The approval process is not a barrier to their use."
Ardern said the arrival of Omicron seemed to have encouraged many people to get the third shots today.
The PM said campaigns such as a "vaxathon" day would not be ruled out.
"We have thought about days of action."
She said the basic message to articulate was "two shots for Delta, three for Omicron".
On booster shots, Bloomfield said the current gap of four months between second dose and booster shots was in fact relatively short by international standards.
Although some Australian states have narrowed the gap to three months, Bloomfield said in the United States the intermission was five months.
Bloomfield said when it came to gaps between first and second shots, he'd requested officials to investigate what the best interval would be for children aged 5 to 11.
Bloomfield said people at higher risk of catching Covid-19, including senior citizens, should, where possible, limit exposure opportunities.
"But I wouldn't describe that as hunkering down for the next four to six weeks," he said.
Ardern also addressed an incident when her vehicle was targeted by hostile people in Paihia.
She said she was never concerned about her safety at the time.
"We are in an environment that does have an intensity to it, which is unusual for New Zealand."
On MIQ, Ardern said international border restrictions had greatly slowed the incursion of virus strains.
"We set out that plan at the end of last year," the PM said. "It's [staged] at allowing individuals to isolate at home once they've entered the country."
She said re-opening plans must progress, but be staged cautiously, in ways that did not endanger the wider public's health and safety.
"Our goal is to make sure that we are slowing it down," the PM said on thwarting Omicron.
"We want our health system to be supported."
'Omicron source may never be established'
Ardern also said the source of the current Omicron outbreak may never be established.
"We know from overseas experience that time's of the essence with Omicron."
She urged anyone eligible for a booster shot to get one as soon as possible.
"As we saw with Delta around the world, high rates of vaccination ... play a major role in preventing widespread outbreaks."
Ardern addressed media at the Beehive this afternoon.
The country is in its second full day under nationwide red traffic light restrictions, where gatherings of more than 100 people are banned.
New Zealand is currently in the first stage of the Government's planned response to Omicron.
The stage is effectively the same elimination strategy used against earlier variants, but Ardern has signalled wiping out Omicron in the medium-term will not be possible.
As a result, the Government anticipates moving to a second, transitional stage once daily cases exceed 1000, perhaps in a few weeks.
The intermediate stage is so far not clearly defined but will include adjusting health measures to focus on people at greater risk of severe illness from Omicron.
The third stage, if cases are in the thousands, will redefine tracing, contacts and isolation requirements.
Some third stage details will probably be revealed tomorrow, when Associate Minister of Health Dr Ayesha Verrall and Bloomfield are expected to address media.
Genome sequencing experts have told the Herald that refining contact definitions and more efficiently tracking contacts will be essential to stop the tracing system failing under the strain of many cases.
Ardern on Sunday indicated advice on face mask use would be assessed and updated if necessary this week.
The PM said any change to mask advice would depend on evidence gathered from overseas about which masks were most effective against the virus.
The National Party today beseeched the Government to move fast on Covid-19 treatments, including the drugs Lagevrio and Paxlovid.
National's pandemic response spokesman Chris Bishop today said both these treatments were approved for use in Britain and the US.
"With Omicron now in our community and with cases likely to increase quickly, we need access to these next generation Covid-19 treatments fast."
He said initial results showed Paxlovid massively reduced hospital admissions among Covid-positive people who were at high risk of severe illness.
Bishop said New Zealand purchased 60,000 courses but Paxlovid was not approved here yet and supply would not arrive until April.
The US Food and Drug Administration said Paxlovid contained a medication to stop Covid-19 from replicating, and was taken as three tablets.
Medsafe's website today said Paxlovid was indicated for the treatment of adult patients with symptomatic confirmed Covid-19 infection.
"Pfizer has provided some data to Medsafe for the rolling assessment but still needs to provide further data as it becomes available," the Medsafe site added.